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Static Var Compensators Protection Scheme Study STATIC VAR COMPENSATORS PROTECTION SCHEME STUDY CASE STUDY: MAHADIYA SUBSTATION SVC By MOHAMMED ESSAM ELDIEN MOHAMMED ELAHAJ IBRAHEM INDEX NO 124082 Supervisor Dr. Elfadil Zakaria Yahia A REPORT SUBMITTED TO University of Khartoum In partial fulfillment for the degree of B.Sc. (HONS) Electrical and Electronics Engineering (POWER ENGINEERING) Faculty of Engineering Department of Electrical and Electronics Engineering October 2017 DECLARATION OF ORGINALITY I declare this report entitled “Static VAR compensators protection scheme study” is our own work except as cited in references. The report has been not accepted for any degree and it is not being submitted currently in candidature for any degree or other reward. Signature: ____________________ Name: _______________________ Date: _______________________ ii ACKNOWLEDGEMENT First, all praise and thanks to Allah for providing me with this opportunity and granting me the capability to proceed successfully. To my mother, who brought to life and raised me to be the man that I am today. To my father who taught me the patience and self-confidence. I would like to express my very great appreciation to Dr. Elfadil Zakaria Yahia my supervisor for his valuable and constructive suggestions during the planning and development of this project Many thanks to my seniors ENG Azza Gasim alsaid for the great guidance and effort. Special thanks to my project partner for his hard work, support and cooperation. iii Abstract In this project the protection scheme of the static VAR compensators of the MAHADYIA substation has been studied. Power system stability is very important, so SVC plays a major role in voltage regulation and improving the stability of the system due to its fast response and high capability. So, it’s very important to make sure that the SVC functions well under normal conditions in order for the electric power to be delivered with high quality to the consumers. Even if there is any abnormal condition, maintenance must be provided. Main principles of operation for protection system beside the historical background of reactive power compensation and overview of static VAR compensators were discussed to illustrate the protection of the SVC. Collecting the data required from MAHADIYA substation, and all calculations of the protective relays have been performed to study the protection scheme. Simulation of this protection scheme has been performed using ETAP software and different scenarios of abnormal condition such as injecting three-phase fault were created to analyze the behavior of relays and circuit breakers. The time of operation for relays to trip the circuit were found suitable to ensure that the SVC is will be safe in abnormal condition. Protection scheme of MAHADIYA substation were studied and simulated. iv المستخلص تم في هذا المشروع دراسة مخطط الحماية للمعوضات الساكنة للقدرة الراجعة لمحطة المهدية بأمدرمان .اﻻستقرار في أنظمة القدرة يعتبر من أهم المعايير ولذلك تعتبر المعوضات الساكنة للقدرة الراجعة من أهم اﻷجهزة التي تساعد في الحفاظ على ذلك اﻻستقرار ويعزى ذلك ﻹستجابتها السريعة وقدرتها العالية كما أنها تلعب دوراً أساسياً في تقويم الجهد. لذلك كان ﻻبد لنا من التاكد أن هذة المعوضات تعمل بالصورة المطلوبة تحت الظروف الطبيعية لنتمكن من تزيود المستهلك بالقدرة الكهربائية المطلوبة وبكفاءة عالية. حتى في حالة اﻷعطال ﻻبد من توافر الصيانة الفورية لكي ﻻ يحدث خلل في اﻹمداد تم دراسة المباديء اﻷساسية للحماية كما تم ذكر خلفية تاريخية عن تعويض القدرة الراجعة للتمهيد لدراسة حماية هذة المعوضات . كما تم جمع البيانات المطلوبة من محطة المهدية وإجراء الحسابات المطلوبة لمرحﻻت الحماية لدراسة مخطط الحماية لهذة المعوضات. تم محاكاة هذا المخطط بإستخدام برنامج إيتاب وأجريت العديد من السيناريوهات لحاﻻت غير طبيعية كحقن خطأ ثﻻثي اﻷطوار لتحليل سلوك المرحﻻت وقواطع الدارات. الزمن الذي يستغرقة المرحل لقطع التيار الكهربي بإستخدام قواطع الدارات وجد مناسبا ً لكي تظل هذة المعوضات أمنة وسليمة في حالة الظروف غير الطبيعية. تم دراسة ومحاكاة مخطط الحماية لهذة المعوضات بمحطة المهدية. v Table of contents DECLARATION OF ORGINALITY................................................................................................... ii ACKNOWLEDGEMENT .................................................................................................................... iii Abstract .................................................................................................................................................. iv v ................................................................................................................................................المستخلص Table of contents .................................................................................................................................... vi List of figures ......................................................................................................................................... ix List of tables ........................................................................................................................................... xi List of abbreviation and terminologies ............................................................................................... xii CHAPTER ONE: Introduction ............................................................. 1 1.1 Overview ..................................................................................................................................... 1 1.2 Problem Statement .................................................................................................................... 1 1.3 Objectives ................................................................................................................................... 1 1.4 Methodology ............................................................................................................................... 1 1.5 Thesis Layout ............................................................................................................................. 1 CHAPTER TWO: Literature Review ................................................. 3 2.1 Reactive power compensation: ................................................................................................. 3 2.1.1 Principles of the Series Controllers ........................................................................................................ 3 2.1.2 Principles of the Shunt Controllers ........................................................................................................ 3 2.1.3 Principles of the Combined Series-Series Controllers ........................................................................... 4 2.1.4 Principles of Combined Series-Shunt Controllers ................................................................................. 4 2.2 Flexible AC Transmission Systems .......................................................................................... 4 2.2.1 Definition of FACTS ............................................................................................................................. 4 2.2.2 FACTS Categories ................................................................................................................................. 5 2.3 Static VAR Compensator (SVC): ............................................................................................. 6 vi 2.3.1 Types of SVC ........................................................................................................................................ 6 2.4 SVC Common used elements: .................................................................................................. 7 2.4.1 Thyristor-controlled reactor (TCR) ........................................................................................................ 7 2.4.2 Thyristor-switched capacitor (TSC):................................................................................................. 12 2.4.3 Mechanically switched capacitor (MSC): ............................................................................................ 14 2.5 Application of static VAR compensators: .......................................................................... 15 2.6 Protection of power system: .................................................................................................... 15 2.6.1 Protection Equipment: ......................................................................................................................... 16 2.7 SVC protection: ....................................................................................................................... 18 2.7.1 Transformer and Bus-Bar Protection: .................................................................................................. 18 2.7.2 TCR Protection .................................................................................................................................... 21 2.7.3 TSC Protection ..................................................................................................................................... 22 2.7.4 Harmonic Filter Protection .................................................................................................................. 22 2.7.5 Auxiliary Transformer Protection ........................................................................................................ 23 2.7.6 Ground Fault Detection ....................................................................................................................... 24 2.7.7 Protective Control Features in SVC control system ...........................................................................
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